Standard library header <numbers> (C++20)
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This header is part of the numeric library.
[edit] Mathematical constants (since C++20)
The header <numbers> provides several mathematical constants, such as std::numbers::pi or std::numbers::sqrt2
[edit] Synopsis
namespace std::numbers { template<class T> inline constexpr T e_v = /* unspecified */; template<class T> inline constexpr T log2e_v = /* unspecified */; template<class T> inline constexpr T log10e_v = /* unspecified */; template<class T> inline constexpr T pi_v = /* unspecified */; template<class T> inline constexpr T inv_pi_v = /* unspecified */; template<class T> inline constexpr T inv_sqrtpi_v = /* unspecified */; template<class T> inline constexpr T ln2_v = /* unspecified */; template<class T> inline constexpr T ln10_v = /* unspecified */; template<class T> inline constexpr T sqrt2_v = /* unspecified */; template<class T> inline constexpr T sqrt3_v = /* unspecified */; template<class T> inline constexpr T inv_sqrt3_v = /* unspecified */; template<class T> inline constexpr T egamma_v = /* unspecified */; template<class T> inline constexpr T phi_v = /* unspecified */; template<floating_point T> inline constexpr T e_v<T> = /* see description */; template<floating_point T> inline constexpr T log2e_v<T> = /* see description */; template<floating_point T> inline constexpr T log10e_v<T> = /* see description */; template<floating_point T> inline constexpr T pi_v<T> = /* see description */; template<floating_point T> inline constexpr T inv_pi_v<T> = /* see description */; template<floating_point T> inline constexpr T inv_sqrtpi_v<T> = /* see description */; template<floating_point T> inline constexpr T ln2_v<T> = /* see description */; template<floating_point T> inline constexpr T ln10_v<T> = /* see description */; template<floating_point T> inline constexpr T sqrt2_v<T> = /* see description */; template<floating_point T> inline constexpr T sqrt3_v<T> = /* see description */; template<floating_point T> inline constexpr T inv_sqrt3_v<T> = /* see description */; template<floating_point T> inline constexpr T egamma_v<T> = /* see description */; template<floating_point T> inline constexpr T phi_v<T> = /* see description */; inline constexpr double e = e_v<double>; inline constexpr double log2e = log2e_v<double>; inline constexpr double log10e = log10e_v<double>; inline constexpr double pi = pi_v<double>; inline constexpr double inv_pi = inv_pi_v<double>; inline constexpr double inv_sqrtpi = inv_sqrtpi_v<double>; inline constexpr double ln2 = ln2_v<double>; inline constexpr double ln10 = ln10_v<double>; inline constexpr double sqrt2 = sqrt2_v<double>; inline constexpr double sqrt3 = sqrt3_v<double>; inline constexpr double inv_sqrt3 = inv_sqrt3_v<double>; inline constexpr double egamma = egamma_v<double>; inline constexpr double phi = phi_v<double>; }